Abstract out the splashscreen delay

Details

Description

Currently to use the splashscreen, you have to add a delay.

appView.loadUrl('foo.bar', 3000);

It would be good to specify initialDelay as a property in config.xml and to have it run the first time loadUrl was added. This is a new feature, so it won't land until after 3.1.0, but it did come up during the 3.0 plugin breakout.